Technical Field
The present invention relates to a sensor including a metal oxide film and use thereof and, more specifically, to a sensor including a metal oxide film formed by wet processing and capable of detecting light, hydrogen gas, and air pressure, a method for fabricating such a sensor, and a method for detecting a concentration of hydrogen gas etc. by using such a sensor.
Related Art
Optical sensors are widely used for optical communications compliant with IrDA (Infrared Data Association) etc., such as television and audio infrared remote controllers, office automation equipment, industrial equipment, consumer equipment, etc.
Further, hydrogen gas has drawn attention as clean and recyclable energy. However, hydrogen gas is known to be highly explosive. Therefore, in order for hydrogen gas to be widely used as a source of energy in the future, it is critical to take safety measures to safely utilize a system. As a tool that contributes to such safety measures, hydrogen gas detection sensors have increased in importance. Under such circumstances, various types of hydrogen gas detection sensor have recently been developed.
Known examples of optical sensors include an optical sensor (Patent Literature 1) using a photovoltaic element composed of a semiconductor laminate, an optical sensor (Patent Literature 2) which has an amorphous semiconductor film used as a photoconductive film and which detects a photo current based on light with which the amorphous semiconductor film has been irradiated, an optical irradiation position detection sensor (Patent Literature 3) constituted by a structure having a predetermined regularity, etc. These sensors have been developed for the purpose of, for example, making high accuracy and long-term highly-sensitive optical detection possible.
Further, known examples of hydrogen gas detection sensors include a sensor (Patent Literature 4) using a hydrogen storing alloy thin film, a sensor (Patent Literature 5) which detects a change in resistance caused by hydrogenaration of a sensing film surface having photoemissive particles dispersed thereon, etc. These sensors have been developed for the purpose of accurately measuring gas concentrations with less power consumption while keeping detection sensitivity and for stably detecting hydrogen gas leaks with reduced variation in electric conductivity.